Fractional esters of polycarboxy acids with certain tetralols



United States Patent CTIONAL ESTERS F POLYCARBOXY ACIDS WITH CERTAIN TETRALOLS Melvin De Groote, St. Louis, Mo., assignor to Petrolite Corporation, a corporation of Delaware N0 Drawing. Original application December 1, 1950,

Serial No. 198,754. Divided and this application December 2, 1952, Serial No. 323,730

8 Claims. (Cl. 260475) The present invention is concerned with certain new chemical products, compounds or compositions which have useful application in various arts.

The particular compounds subsequently described herein in greater detail are hydrophile synthetic products, and more particularly, fractional esters obtained from a polycarboxy acid and a tetralol, i. e., the chemical compound having 4 alkanol hydroxyls comparable to diols and triols. The particular hydroxylated compound herein employed is obtained by reaction between a polypropylene glycol of comparatively high molecular weight, for example 7505,000, with two moles of glycide, thus converting a diol into a tetralol.

The products of this invention have particular value as demulsifying agents in a process for resolving petroleurn emulsions of the water-in-oil type that are commonly referred to as cut oil, roily o' emulsified oil, etc., and which comprise fine droplets of naturallyoccurring waters or brines dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion. A process for resolving petroleum emulsions of the water-in-oil type which utilizes the products described herein is described and claimed in my copending application Serial No. 198,754, filed December 1, 1950, now U. S. Patent 2,626,903 of which the present application is adivision. Application Serial No. 198,754 was copending with and was a continuation-in-part of my application for Patent No. 2,552,528, dated May 15, 1951.

The products are also useful in a process for separating emulsions which have been prepared under controlled conditions from mineral oil, such as crude oil and relatively soft waters or weak brines. Controlled emulsification and subsequent demulsification under the conditions just mentioned are of significant value in removing impurities, particularly inorganic salts from pipeline oil. They are also useful for other purposes, such as stabilizing emulsions, as Spreaders in the application of asphalt in road building and the like, as flotation reagents, as lubricants, etc.

My aforementioned Patent No. 2,552,528 is concerned with a process for breaking petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including high molal oxypropylation derivatives of a member of the class consisting of monomeric polyhydric compounds and monomeric polyhydric derivatives thereof which bear a simple genetic relationship thereto, with the proviso that 2 molecular weight range of 2000 to 30,000 on an average statistical basis;

(f) the solubility characteristics of the oxypropylation end product in respect to water and Xylene be substantially the result of the oxypropylation step;

(g) the ratio of propylene oxide per hydroxyl in the initial polyhydric reactant be within the range of 7 to with the proviso that n is a large number sufiicient to bring the molecular weight range of the polypropylene glycol within the molecular weight range of 750-5,000.

Incidentally, my preferred range is approximately 1750 to 2750.

If one mole of such diol were etherized with 2 moles of glycerol or, what amounts to the same thing, reacted with 2 moles of glycidc, the reaction product, or at least one of the reaction products. may be indicated as follows:

HO OH As will be pointed out subsequently and what is obvious is the fact that polypropylene glycol may have two terminal secondary alcohol radicals, or two terminal primary alcohol radicals, or one terminal primary alcohol radical and one terminal secondary alcohol radical.

Thus, the previous formula is based on the assumption that reaction takes place at both terminal hydroxyl radicals which may or may not be the case. If reaction takes place at one terminal hydroxyl only then instead of the previous formula the tetralol would presumably be indicated by the following formula:

HO(RO)C3H5 OH It would be immaterial as to the form of the tetralol and, as a matter vof fact it well may be that cogeneric mixtures are obtained. Thus, it is more satisfactory to indicate the tetralol as being of the following composition: I

' RO(RO)nR with the proviso that R is a radical selected from the monovalent radicals consisting of hydrogen,

CaHs

and

to form a tetralol.

Polypropylene glycols are available from at least two companies- Such polypropylene glycols are furnished in various molecular weight ranges. The water-insoluble, kerosene-soluble polypropylene glycols being in the molecular weight range somewhere above 500, and more specifically, at about 700 or 750. The molecular weight was usually determined by the hydroxyl method. Such hydroxyl molecular weight is a fraction, sometimes a large major fraction, of the theoretical molecular Weight based on the method of synthesis, i. e., the calculated molecular weight based theoretically on the value one would expect to obtain by treating water or propylene glycol, for example, with propylene oxide. Needless to say, one does not obtain a single compound but a propylene glycol of a molecular weight ratio of 750 or 1,000 or 2,000 as the case may be, and really represents a cogeneric mixture whose statistical average molecular weight is the one indicated.

Polypropylene glycols, which are regularly supplied to the trade in volume, include those where the molecular weight runs to 2,000 and beyond. Higher ones are available up to a molecular weight of 3,000 or more. Those of molecular weight of 3,000 to 5,000 can be prepared by conventional means employing substantially the same procedure as polypropylene glycols available on the market. In any event those available on the market, for instance, polypropylene glycol 2,000, is substantially in the center of the preferred range (1750-2750) and thus is perhaps the outstanding raw material commercially available for the herein described purpose.

If a polycarboxy acid for convenience is indicated thus:

COOH

ooonw in which n is a whole number not greater than 2, it becomes obvious that the resultant obtained from treating one mole of the tetralol with 4 moles of a polycarboxy acid may be written thus:

in which all the characters have their previous significance, with the proviso that R'O(RO)1LR"' is the tetravalent radical obtained, at least hypothetically, by the elimination of the hydroxyl hydrogen atoms from the tetralol R'O(RO)nR' as previously described, with the proviso that n represents a whole number varying from one to three and the sum of both occurrences of n is 4.

It is obvious that minor changes can be made which do not detract from the spirit of the invention, for instance, one could start with a mole of ethylene glycol or mole of diethylene glycol and react with polypropylene glycol so as to get a compound which in the strictest; sense of the word is not a polypropylene glycol but for all herein mentioned purposes would meet the requirement as to molecular weight range and solubility. Similarly, one could start with butylene glycol and react with a mole of ethylene oxide and then follow by oxypropylation so as to give a product which again in its strictest sense might not be a polypropylene glycol but yet would be within the molecular weight range and show the same solubility characteristics and be entirely satisfactory. For all practical purposes such compounds by treatment with 2 moles of glycide.

4 are considered as polypropylene glycol for the herein described purpose.

Having obtained the tetralol of the kind described, the product so obtained is converted into an acidic ester by reacting with a polycarboxy acid so as to introduce one mole of the acid for each hydroxyl radical. This is shown by the above formula. Such esterification is conducted under comparatively mild conditions to prevent polymerizing, i. e., the final product is an acidic ester of the hydroxylated material and not a polyester. For convenience, what is said hereinafter will be divided into four sections:

Part 1 is concerned with the preparation of the tetralol from the selected polypropylene glycol;

Part 2 is concerned with the preparation of the esters from the tetralol;

Part 3 is concerned with the structure of the esterified polyhydroxylated compounds and particularly from the standpoint of the polypropylene glycol itself and its relationship to the method of describing the ultimate products; and

Part 4 is concerned with certain derivatives which can be obtained from the tetralols. In some instances such tetrahydroxylated compounds can be reacted further and converted into other intermediates which in turn can be reacted further, as for example, by modest oxyethylation, then with the same polycarboxy acids and anhydrides as described in Part 2.

PART 1 As previously stated the initial step in the manufacture is to either prepare a polypropylene glycol of roughly 7505000 molecular weight which is water-insoluble and kerosene-soluble, or else to purchase such material in the open market. My preference is to purchase such material in which the molecular weight is 2,000 or slightly higher. The next step is to convert this diol into a tetralol Needless to say, other reactions can be employed which do not involve glycide as, for example, one can produce ethers of the kind herein employed by use of a glycerol monochlorohydrin either alphaor beta-monochlorohydrin. Attention is directed to the fact that it would be immaterial as to whether a derivative were obtained from the alphaor betaglycerol monochlorohydrin. Similarly, a similar isomeric difference can occur depending on how the epoxy ring is ruptured in the case of glycide. Other suitable procedures involve the use of epichlorohydrin in the conventional manner. In some instances this would involve an intermediate step of converting the diol into an alkoxide. Other procedures would involve the use of epichlorohydrin with the resultant product treated with caustic soda so as to reform the expoxy ring. The epoxide so obtained could then be treated with water to yield a compound having more than one hydroxyl radical and, at least, one of the two initial terminal hydroxyls attached to the polypropylene glycol.

Attention is directed to the fact that the use of glycide requires extreme caution. This is particularly true on any scale other than small laboratory or semi-pilot plant operations. Purely from the standpoint of safety in the handling of glycide, attention is directed to the following: (a) If prepared from glycerol monochlorohydrin, this product should be comparatively pure; ([2) the glycide itself should be as pure as possible as the eifect of impurities is difficult to evaluate; (c) the glycide should be introduced carefully and precaution should be taken that it reacts as promptly as introduced, i. e., that no excess of glycide is allowed to accumulate; (d) all necessary precaution should be taken that glycide cannot polymerize per se; (e) due to the high boiling point of glycide one can readily employ a typical separatable glass resin pot as described in U. S. Patent No. 2,499,370, dated March 7, 1950, to DeGroote and Keiser, and oifered for sale by numerous laboratory supply houses. If such arrangement is used to prepare laboratory-scale duplications, then care should be taken that the heating mantle can be removed rapidly so as to allow for cooling; or better still, through an added opening at the top, the glass resin pot or comparable vessel should be equipped with a stainless steel cooling coil so that the pot can be cooled more rapidly than by mere removal of mantle. If a stainless steel coil is introduced it means that conventional stirrer of the paddle type is changed into the centrifugal type which causes the fluid or reactants to mix due to swirling action in the center of the pot. Still better, is the use of a laboratory autoclave of the kind offered for sale by a number of laboratory supply houses; but in any event, when the initial amount of glycide is added to a suitable reactant, such as a polypropylene glycol of the kind described preceding, the speed of reaction should be controlled by the usual factors, such as (a) the addition of glycide; (b) the elimination of external heat; and (c) the use of cooling coil so there Alltheforegoing is I is no undue rise in temperature. I

merely conventional but is included due to the hazard in handling glycide. I

Example 1a The equipment used was a glass pot of the kind above described. 'This particular pot had a capacity of about p 1500 ml. The polypropylene glycol selected was a commercial product described as polypropylene glycol 2025. Thisvalue was the same as the molecular weight based on the hydroxyl value. The ratio of glycide to diol is obviously.2 to l to produce a tetralol. The amount of polypropylene glycol taken was one-half of a gram mole, i. e., 1015 grams. This was reacted with one gram mole of glycide (74 grams). The procedure was as follows: The polypropylene glycol was charged into the reaction vessel along with 1% (10.5 grams) of sodium methylate. The mixture was stirred and the temperature raised to about 120 C. The glycide was placed drop-wise into the reaction mixture with constant stirring at a comparatively low rate, i. e., about grams per hour. The entire reaction required approximately 5 hours. The temperature during the reaction was allowed to rise to 130 C. At any time it tended to go higher it was cooled in an appropriatemanner. If the temperature tended to drop below 112 to 115 C., "the reaction mass was heated. When all the glycide had been added the reaction mass was stirred for approximately an hourlonger at 130 C. and then heated to a temperature below the decomposition point of glycide, for instance, 140 C., and held at this higher temperature for another hour. In this particular reaction there was comparatively little hazard due to the small amounts of glycide involved. Even so, such oxyalkylation should be conducted with extremecare.

Example 2a Example 3a The same procedure was followed as in Examples 1a and 2a, preceding, exceptjthat the polypropylene glycol used was one having a molecular weight of 2750. The amount employed was 1375 grams. The amount of catalyst employed (sodium methylate) was 14 grams. The amount of glycide employed was identically the same as in Examples la and 2a, preceding. The time factor and temperature were the same as in Examples 1a and 2a, preceding. The heating period after all the glycide Was .inwas the same asin Examples 1a and-2a, preceding. In

I e this-instance, however, the glass reaction pot had a capacity of 2' liters instead of 1%. liters. 1

The tetralols resulting from the above procedures were slightly off-color compared with the original polyproyl- W ene glycol. .A, slight change ,to a faint yellowish cast appeared during the reaction with glycide. product, of course, had a slightly alkaline reaction due to the presence of sodium methylate and this would have been the case also if some other catalyst, such as caustic soda, had been used. i

These tetralols could, .of course, be bleached in the usual manner with a bleaching clay, a filtering char, or the like. For the purpose of producing the demulsifier this was immaterial. --The viscosity of the liquids were somewhat higher than that of the initial diols from which they were obtained. These products, i. e., tetralols, were water-insoluble and kerosene-soluble.

PART 2 As previously pointed out the present invention is concerned with acidic estersobtained from tetralols described in Part 1, preceding, and polycarboxy acids, particularly dicarboxy acids such 'as adipic acid, phthalic acid, or anhydride, succinic acid, diglycollic acid, sebacic acid, azelaicacid, a'conitic acid, maleic acidor anhydride, citraconic acid or anhydride, maleic acid or anhydride adductsas obtained by the Diels-Mder reaction from reactants such as maleic anhydride and cyclopentadiene. Such acids should be heat stable so they are not decomposed during esterification. They may contain as many as 36 carbon atoms as, for example, the acids obtained by dimerization'of unsaturated fatty acids, unsaturated monocarboxy fatty acids, or unsaturated monocarboxy acids having 18 carbon atoms. Reference to the acid in the hereto appended claims obviously includes the anhydrides or any other obvious equivalents. My preference, however, is to use polycarboxy acids having not over 8 carbon atoms.

The production of esters including acid esters (fractional esters) from polycarboxy acids and glycols or other hydroxylated compounds is well known. Needless to say, various compounds may be used such as the low molal ester, the anhydride, the acyl chloride, etc. However, for purpose of economy it is customary to use either the acid or the anhydride. A conventional procedure is employed. On a laboratory scale one can employ a resin pot of the kind described in U. S. Patent No. 2,499,370, dated March 7, 1950, to DeGroote & Keiser, and particularly with one more opening to permit the use of a porous spreader if hydrochloric acid gas is to be used as a catalyst. Such device or absorption spreader consists of minute alundum thimbles which are connected to a glass tube. One can add a sulfonic acid such as paratoluene sulfonic acid as a catalyst. There is some objection to this because in some instances there is some evidence that this acid catalyst tends to decompose or rearrange oxypropylated compounds, and particularly likely to do so if the esterification temperature is too high.' In the .case of polycarboxy acids such as diglycollic acid, which is strongly acidic there is no need to add any catalyst. The use of hydrochloric gas has one advantage over paratoluene sulfonic acid and that is that at the end of the reaction it can be removed by flushing out with nitrogen, Whereas there is no reasonably convenient means available of removing the paratoluene sulfonic acid or other sulfonic acid employed. If hydrochloric acid is employed one need only pass the gas through at an exceedingly slow rate so as to keep the reaction mass acidic. Only a trace of acid need be present. I have employed hydrochloric acid gas or the aqueous acid itself. to eliminate the initial basic material. My

. preference, however, is to use no catalyst whatsoever and to insure complete dryness of the tetralol as described in the text immediately following.

The products obtained Part 1 preceding may con- The final Y 7 tain a basic catalyst. As a general procedure I have added an amount of half-concentrated hydrochloric acid considerably in excess of what is required to neutralize the residual catalyst.- The mixture is shaken thoroughly and allowed to stand overnight. It is then filtered and refluxed with the xylene present until the water can be separated in a phase-separating trap. As soon as the product is substantially free from water the distillation stops. This preliminary step can be carried out in the flask to be used for esterification. If there is any further deposition of'sodium chloride during the reflux stage needless to say a second filtration may be required. In any event the neutral or slightly acidic solution of the tetralols described in Part 1 is then diluted further with sufllcient xylene, decalin, petroleum solvent, or the like, so that one has obtained approximately a 45% solution. To this solution there is added a polycarboxylated reactant as previously described, such as phthalic anhydride, succinic acid or anhydride, diglycollic acid, etc. The mixture is refluxed until esterification is complete as indicated by elimination of water or drop in carboxyl value. Needless to say, if one produces a half-ester from an anhydride such as phthalic anhydride,v no water is eliminated. However, if it is obtained from diglycollic acid, for example, water is eliminated. All such procedures are conventional and have been so thoroughly described in the literature that further consideration will be limited to a few examples and a comprehensive table.

Other procedures for eliminating the basic residual catalyst, if any, can be employed. For example, the oxyalkylation can be conducted in absence of a solvent or the solvent removed after oxypropylation. Such oxypropyla-- tion end product can then be acidified with just enough concentrated hydrochloric acid to just neutralize the residual basic catalyst. To this product one can then add a small amount of anhydrous sodium sulfate (suflicient in quantity to take up any water that is present) and then subject the mass to centrifugal force so as to eliminate the hydrated sodium sulfate and probably the sodium chloride formed. The clear somewhat viscous strawcolored amber liquid so obtained may containa small amount of sodium sulfate or sodium chloride but, in any event, is perfectly acceptable for esterification in the manner described.

It is to be pointed out that the products here described are not polyesters in the sense that there is a plurality of both tetralol radicals and acid radicals; the product is characterized by having only one tetralol radical.

In some instances and, in fact, in many instances I have found that in spite of the dehydration methods employed above that a mere trace of Water still comes through and that thismere trace of water certainly interferes with the acetyl or hydroxyl value determination, at least when a number of conventional procedures are used and may retard esterification, particularly Where there is no sulfonic acid or hydrochloric acid present as a catalyst. Therefore, I have preferred to use the following procedure: I have employed about 200 grams of the tetralol as described in Part 1, preceding; I have added about 60 grams of benzene, and then refluxed this mixture in the glass resin pot using a phase-separating trap until the benzene carried out all the Water present as water of solution or the equivalent. Ordinarily this refluxing temperature is apt to be in the neighborhood of 130to possibly 150 C. When all this water or moisture has been removed I also withdraw approximately 20 grams or a little less benzene and then add the required amount of the carboxy reactant and also about 150 grams of a high boiling aromatic petroleum solvent. These solvents are sold by various oil refineries and, as far as solvent effect act as if they were almost completely aromatic in character. Typical distillation data in the particular type i have employed and found very satisfactory is the following:

I. B. P., 142 C. 50 ml., 242 C. 5 ml., 200 C. 55 ml., 244 C. 1.0 ml., 209 C. 60 ml., 248 C. 15 ml., 215 C. ml., 252 C. 20 ml., 216 C. ml., 252 C. 25 ml., 220 C. .75 ml., 260 C.

30 ml., 225 C. ml., 264 C.

35 ml., 230 C. ml 270 C. 40 ml., 234 C. ml., 280 C. 45 ml., 237 C. ml., 307' C.

After this material is added, refluxing is continued and, of course, is at a higher temperature, to wit, about 160 to 170 C. If the carboxy reactant is an anhydride needless to say no water of reaction appears; if the carboxy reactant is an acid water of reaction should appear and should be eliminated at the above reaction temperature. If it is not eliminated I simply separate out another 10 or 20 cc. of benzene by means of the phase-separatingtrap and thus raise the temperature to 180 or 190 C., or even to 200 C., if need be. My preference is not to go above 200 C.

The use of such solvent is extremely satisfactory provided one does not attempt to remove the solvent subsequently except by vacuum distillation and provided there is no objection to a little residue. Actually, when these materials are used for a purpose such as demulsification the solvent might just as well be allowed to remain. If the solvent is to be removed by distillation, and particularly vacuum distillation, then the high boiling aromatic petroleum solvent might well be replaced by some more expensive solvent, such as decalin or an alkylated decalin which has a rather definite or close range boiling point. The removal of the solvent, of course, is purely a conventional procedure and requires no elaboration.

In the appended table Solvent #7-3, which appears in numerous instances, is a mixture of 7 volumes of the aromatic petroleum solvent previously described and 3 volumes of benzene. Reference to Solvent #7 means the particular petroleum solvent previously described in detail. This was used, or a similar mixture, in the manner previously described. A large number of the examples indicated employing decalin were repeated, using this mixture and particularly with the preliminary step of removing all the water. If one does not intend to remove the solvent my preference is to use the petroleum solventbenzene mixture although obviously any of the other mixtures, such as decalin and xylene, can be employed.

The data included in the subsequent table are selfexplanatory, and very complete and it is believed no further elaboration is necessary:

TABLE 1 Amt. of Max Ex. No. Time of Theo. M01. Amt. of Polycar- Amt. Esteri- Water i gg gi g gg; Wt. of 1 Tetralol gzgggggg Rbmy Solvent Sorvent i ircation Egg; Out ompd Tetralol (Gms.) 5231i; rs.) 8163. (Hm) (00.)

1a 2, 173 Diglycol. Acid. 24 #73 190 15 3. 0 1a 2, 173 100 Phthalic Anhyd... 26. 6 #7-3 175 5 Nil 111 2,173 100 Maleic Anh d. 17. 6 #7-3 116 170 4% Nil la 173 100 succinic An yd..- 18 #7-3 116 4% Nil 1a 2, 173 100 Aconitic Acid 32 #7-3 122 182 4 3.0

' 1 Theoretical molecular weight of tetralol based on hydroxyl value of polypropylene glycol, and assuming complete combination with the glycide.

The procedure for manufacturing'the esters has been illustrated by preceding examples. If for any reason reaction does not take placein amanner that is acceptable, attention should be directed to the following details: (a) Recheck the hydroxyl or acetyl value of the tetraloland use a stoichiometrically equivalent amount of acid; (b) if the reaction does not proceed with reasonable speed either raise the temperature indicated or else extend the period of time up to l2 or 1-6 hours if need be; (c) if necessary, use /2 %v of paratoluene sulfonic acid orl some other acid as a catalyst; (d) if the esterification does not produce a clear product a check should be made to see if an inorganic saltsuch as sodium chloride or sodium sulfate is not precipitating out. Such salt should-be eliminated, at least for explorationexperimentation, and can be removed by filtering. Everything else being equal as the size of the molecule increasesthe reactive hydroxyl radical represents a smaller fraction of the entire molecule and thus more difliculty is involved in obtaining complete esterification.

In some instances an attempt to react the stoichiometric amount of a polycarboxy acid with the tetralol results in an excess of the carboxylated reactant for the reason that apparently under conditions of reaction less reactive hydroxyl radicals are present than indicated by the hydroxyl value. Under such circumstances there is simply a residue of the carboxylic reactant which can be removed by filtration or, if desired, the esterification procedure can be repeated using an appropriately reduced ratio of carboxylic reactant.

Even the determination of the hydroxyl value and conventional procedure leaves much to be desired due either to the cogeneric materials previously referred to, or for that matter, the presence of any inorganic salts or propylene oxide. Obviously this oxide should be eliminated.

The solvent employed, if any, can be removed from the finished ester by distillation and particularly vacuum distillation. The final products or liquids are generally almost water-white to a very pale straw color, and show moderate viscosity. They can be bleached with bleaching clays, filtering chars, and the like. However, for the purpose of demulsification or the like color is not a factor and decolorization is not justified.

In the above instance I have permitted the solvents to remain present in the final reaction mass. In other instances I have followed the same procedure using decalin or a mixture of decalin or benzene in the same manner and ultimately removed all the solvents by vacuum distillation.

PART 3 In the hereto appended claims the products are described as acidic esters obtained from a material having 4 hydroxyl radicals. The tetralol used to produce the ester is, in turn, obtained from a polypropylated glycol.

Oxypropylation is obviously involved in the preparation of high molal polypropylene glycols of the kind herein employed as raw materials. Propylene glycol has a secondary alcoholic radical and a primary alcohol radical. Obviously then polypropylene glycols could be obtained, at least theoretically, in which two secondary alcoholic groups are united or a secondary alcohol group is united to a primary alcohol group, etherization being involved, of course, in each instance. Needless to say, the same situation applies when one reacts such glycols to produce polyhydric materials having 4 or more hydroxyls.

The significant fact is in regard to the glycerol or glycide ethers of the polypropylene glycols herein specitied that although they are obtained from initial products which are water-soluble, i. e., water, propylene glycol or the like, yet these tetralols prior to esterification are water-insoluble and kerosene-soluble. Needless to say, treatment of any chemical compound with 1, 2 or 3 moles of glycide tendsto' increase water-solubility and decrease kerosene-solubility. Incidentally, too, the initial products prior to oxypropylation are'not xylenesoluble, that is, waterand propylene glycol are not xylene-soluble, butthe final products are.. When polypropylene glycols of comparatively .low molecular weight, about 700, are employed, they produce tetralols which sometimes may tend to emulsify or disperse somewhat in water because some of the constituents, being a cogeneric mixture, are water-soluble but the bulk are waterinsoluble. Thus in the low molecular weight tetralols one may have some emulsification or dispersibility in water, as noted. This is not true, however, in my preferred range, i. e., 1750 to 2750. I have found these particular tetralols to be most desirable for preparing the ester.

Going back to what has. been said previously in the introductory part it will be noted that one may have variations in regard to'how the glycide combines to form the tetralol. Thus, the formula as herein employed and particularly the claims, mustbeinterpreted in light of the facts previously indicated namely (a) there may be a considerable variation in the structure of a polypropylene glycol as to whether one has a head-to-tail structure, a tail-to-tail structure, or a head-to-head structure, or other variations; (b) variation will take place in the total range, for example, in an instance where It might statistically average 40 the actual variation of n might run from 20 to 60, and (c) the manner in which the glycide combines to produce a tetralol may vary also as has been pointed out. These facts must be considered in the descriptions herein employed, both in the specifications and in the claims. For obvious reasons no better characterization is available.

PART 4 Previous reference has been made to oxyalkylated agents other than propylene oxide and glycide, for example, ethylene oxide and butylene oxide. Obviously variants can be prepared, which do not depart from what has been said herein, to produce compounds of the described structure. The tetralols could be treated with one or more moles of ethylene oxide to yield a product in which water-solubility and kerosene-solubility have not been particularly aifected. Such tetralol could then be combined to give the acidic fractional ester corresponding to those herein described. The molecular weight range of the tetralol would obviously be within the described limits. Instead of ethylene oxide one might employ butylene oxide. In such variations other comparable ones can be employed without departing from the spirit of the invention.

Incidentally, the polyhydroxylated materials described in Part 1 can be treated with various reactants such as epichlorohydrin, dirnethyl sulfate, sulfuric acid, ethylene imine, etc., to give new intermediates of obvious values for organic synthesis. If treated with epichlorohydrin or monochloracetic acid the resultant product can be further reacted with a tertiary amine, such as pyridine, or the like, to give ammonium compounds. If treated with maleic anhydride to give a total ester the resultant can be treated with sodium bisulfite to yield a sulfosuccinate. Sulfo groups can be introduced also by means of a sulfating agent as previously suggested, or by treating the chloroacetic acid resultant with sodium sulfite.

I have found that if such hydroxylated compound or compounds are reacted further so as to produce entirely new derivatives, such new derivatives have the properties of the original hydroxylated compound to some degree and yet in other ways are markedly different. This is especially true insofar that they are eifective and valuable demulsifying agents in many instances for resolution of water-in-oil emulsions as found in the petroleum industry, as break-inducers in doctor treatment of sour crude, etc.

11 Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. Hydrophile synthetic products; said hydrophile synthetic products being fractional esters of (A) a polycarboxy acid selected from the class consisting of acyclic and isocyclic dicarboxy. and tricarboxy acids composed of carbon, hydrogen and oxygen and having not more than 8 carbon atoms with (B) a tetralol selected from the class consisting of tetralols of the formula H0(CaHa0)r-CaH5 OH OCaH5 HO OH 0311 0 (C3HBO)7|C3H5 HO OH in which n is a number so selected that the corresponding compound HO(CaHsO)nH has a molecular weight within the approximate range 750 to 5000, with the proviso that the molar ratio of (A) to (B) be 4: 1.

2. Products as in claim 1 in which n is so selected that the corresponding compound HO(C3H60)nH has a molecular weight within the approximate range of 1750 to 2750.

3. The products as in claim 1 in which n is so selected that the corresponding compound HO(C3H60)nH has a molecular weight within the approximate range of 1750 to 2750 and the polycarboxy acid is a dicarboxy acid.

4. The products of claim 3 wherein the dicarboxy acid is diglycollic acid.

5. The products of claim 3 wherein the dicarboxy acid is phthalic acid.

6. The products of claim 3 wherein the dicarboxy acid is maleic acid.

7. The products of claim 3 wherein the dicarboxy acid is succinic acid.

v 8. The products of claim 3 wherein the dicarboxy acid is citraconic acid.

No references cited. 

1. HYDROPHILE SYNTHETIC PRODUCTS; SAID HYDROPHILE SYNTHETIC PRODUCTS BEING FRACTIONAL ESTERS OF (A) A POLYCARBOXY ACID SELECTED FROM THE CLASS CONSISTING OF ACYCLIC AD ISOCYCLIC DICARBOXY AND TRICARBOXY ACIDS COMPOSED OF CARBON, HYDROGEN AND OXYGEN AND HAVING NOT MORE THAN 8 CARBON ATOMS WITH (B) A TETRALOL SELECTED FROM THE CLASS CONSISTING OF TETRALOLS OF THE FORMULA 